The left auricular appendage in mitral stenosis.

Since the introduction of the operation of mitral valvotomy much interest has been aroused'in the histological changes found in biopsy specimens of the left auricular appendage. Some workers have recorded a high incidence of lesions resembling Aschoff nodules, and since these are found in patients in whom no rheumatic activity is apparent clinically, there has been much speculation as to their precise nature and significance. A review of the histological studies of rheumatic heart disease gives no indication of the frequency with which the appendage is involved in active carditis, nor of the morphology of the specific lesions in this site, since the appendage is not usually examined histologically. It is the purpose of this investigation, therefore, not only to record the findings in biopsy specimens of the left auricular appendage from patients who have had valvotomy, but also to study the appendage in patients who have died with mitral stenosis, in order to assess the full significance of the various lesions observed in this structure in patients suffering from chronic rheumatic heart disease.